| Literature DB >> 28710225 |
Mariusz T Grzeda1, Jon Heron1, Kate Tilling1, Anne Wright2, Carol Joinson1.
Abstract
OBJECTIVE: To examine whether a range of common strategies used by parents to overcome bedwetting in 7½-year-old children (including lifting, restricting drinks before bedtime, regular daytime toilet trips, rewards, showing displeasure and using protection pants) are effective in reducing the risk of bedwetting at 9½ years.Entities:
Keywords: ALSPAC; bedwetting; child; cohort study; prevention
Mesh:
Year: 2017 PMID: 28710225 PMCID: PMC5541498 DOI: 10.1136/bmjopen-2017-016749
Source DB: PubMed Journal: BMJ Open ISSN: 2044-6055 Impact factor: 2.692
Associations between the parental strategies used to overcome bedwetting in children at 7½ years (n=1258)
| Lifting child out of bed to use toilet | Restricting drinks before bedtime | Regular daytime toilet trips | Rewarding child for being dry | Showing displeasure when child wets bed | Using night-time protection pants/nappies | Medication for bedwetting | Bedwetting alarm | |
| Lifting | 1.000 | |||||||
| Restricting drinks | 0.509 | 1.000 | ||||||
| Daytime toilet trips | 0.295 | 0.413 | 1.000 | |||||
| Rewards | 0.444 | 0.407 | 0.523 | 1.000 | ||||
| Showing displeasure | 0.236 | 0.456 | 0.323 | 0.345 | 1.000 | |||
| Protection pants | −0.038 | −0.151 | 0.231 | 0.249 | 0.040 | 1.000 | ||
| Medication | 0.238 | 0.164 | 0.416 | 0.423 | 0.016 | 0.296 | 1.000 | |
| Bedwetting alarm | 0.050 | −0.099 | 0.230 | 0.492 | −0.070 | 0.230 | 0.113 | 1.000 |
The associations between strategies are tetrachoric correlation coefficients. These are correlation coefficients of binary variables. The tetrachoric correlation coefficient provides an estimate of what the correlation would be if the variables were measured on a continuous scale. The size of the tetrachoric correlation coefficient can be interpreted in the same way as a correlation coefficient between two continuous variables, that is, ‘0’ indicates no correlation and ‘1’ indicates perfect correlation.
All coefficients were computed on the baseline sample.
Characteristics of the study participants at 7½ and 9½ years
| 7½ years | 9½ years | |
| Gender | ||
| Female | 33.2% | 32.8% |
| Male | 66.8% | 67.2% |
| n | 1258 | 1045 |
| Social class* | ||
| Non-manual (professional, managerial, skilled professions) | 82.0% | 82.3% |
| Manual (partly or unskilled occupations) | 18.0% | 17.7% |
| n | 1094 | 923 |
| Home ownership* | ||
| Owner/occupier | 85.5% | 87.5% |
| Rented accommodation | 14.5% | 12.5% |
| n | 1112 | 952 |
| Car access* | ||
| Yes | 91.1% | 91.8% |
| No | 8.9% | 8.2% |
| n | 1132 | 965 |
| Maternal education* | ||
| A-level or above | 43.9% | 46.9% |
| O-level | 33.6% | 33.4% |
| Certificate of secondary school/vocational/none | 22.5% | 19.7% |
| n | 1226 | 1021 |
*These variables were derived from responses to a questionnaire completed by mothers during the antenatal period.
Figure 1Prevalence of parental strategies for overcoming bedwetting (A) and prevalence of children with parents employing a given number of strategies (B).
Estimated differences in the risk of bedwetting at 9½ years in children whose parents used each strategy compared with those who did not use the strategy
| Average treatment effect on treated (95% CI) based on inverse probability weighting using propensity score | Average treatment effect/adjusted risk difference (95% CI) based on logistic regression analysis | |||||
| Empty (unadjusted) model* | Model adjusted for child and family variables | Model adjusted for child and family variables and other parental strategies | Empty (unadjusted) model | Model adjusted for child and family variables | Model adjusted for child and family variables and other parental strategies | |
| Lifting | 0.251 | 0.148 | 0.106 | 0.251 | 0.172 | 0.125 |
| Restricting drinks | 0.173 | 0.138 | 0.123 | 0.173 | 0.147 | 0.112 |
| Daytime toilet trips | 0.198 | 0.088 | 0.068 | 0.198 | 0.087 | 0.057 |
| Rewards | 0.281 | 0.141 | 0.088 | 0.281 | 0.158 | 0.143 |
| Showing displeasure | 0.054 | 0.009 | −0.052 | 0.054 | 0.009 | −0.047 |
| Protection pants | 0.290 | −0.010 | −0.010 | 0.290 | 0.025 | 0.025 |
The estimates provided in this table are average treatment effects for each strategy. They are risk differences, that is, estimated differences between the risk of bedwetting at 9½ years after receiving given ‘treatment’ (ie, parental strategy) and the risk of bedwetting if they had remained ‘untreated’. We provide examples of how to interpret the risk differences below:
(1) The risk difference for ‘restricting drinks’ (0.123 (95% CI 0.021 to 0.226)) shows that there is a 12.3% (2.1% to 22.6%) increase in risk of bedwetting at 9½ years among children whose parents used restricting drinks compared with children whose parents did not use this strategy.
(2) The risk difference for ‘showing displeasure’ (−0.052 (−0.214 to 0.11)) shows that there is a 5.2% reduction in the risk of bedwetting at 9 years among children whose parents show displeasure, but the 95% CI indicates that this result could be in either direction (between a 21% reduced risk and 11% increased risk).
*Empty model column for propensity score-based methods analysis shows unadjusted differences in risk of bedwetting between ‘treated’ and ‘untreated’ children. These coefficients are equivalent to bivariate regressions including bedwetting at 9½ years as an outcome variable and each strategy as a single predictor.
†Model adjusted for child and family variables represents average treatment effects on treated children. These coefficients are estimated differences in risks of bedwetting in weighted samples. These are differences in risks adjusted for child and family variables that accounted for the differences between treated and untreated groups and between those with and without bedwetting at age 9½. The list of child and family variables was derived separately for every strategy on the basis of ORs from regression analyses providing evidence of an association (ORs <0.90 or >1.20) both with the given strategy and with bedwetting at age 9½. A detailed list of child and family variables included in the model for each parental strategy is provided in the online supplementary material (see online supplementary table S2–S7).
‡Model adjusted for child and family variables and other parental strategies. This is the column with coefficients adjusted for the child and family variables and for other parental strategies that were highly correlated (coefficient of tetrachoric correlation >0.45) with given strategy.
§Empty model: results of univariable logistic regression analyses including bedwetting at 9½ years as an outcome variable and the given strategy as a single predictor. To ensure direct comparisons with the output of the analysis using propensity score-based methods, the results of regression analyses are expressed here in terms of risk differences instead of ORs.
¶ Model adjusted for child and family variables. This includes estimated differences in risk of bedwetting for given strategy obtained from logistic regression, also including child and family variables.
**Model adjusted for child and family variables and other parental strategies. Risk differences for given strategy obtained from logistic regression including child and family variables and other strategies associated with the strategy under examination.
††Indicates risk differences that provide evidence for an increase in bedwetting associated with the parental strategy.
Figure 2Estimated differences in the risk of bedwetting at 9½ years in children whose parents used each strategy compared with those who did not use the strategy: results of the propensity score-based model (A) and the logistic regression analysis (B).